Pressure regulating and reducing apparatus



Nov. 7, 1939. G. H. SMITH a-r A1. 2,178,974

PRESSURE REGULATING AND REDUCING APPARATUS Original Filed Jan. 31, 19332 Sheets-Sheet 1 IWI ILIl r ATTO RNEY Nov. 7, 1939.

Original Filed Jan. 31,

GJ H. SMITH r AL PRESSURE REGULATING AND REDUCING APPARATUS 1933 v2Sheets-Sheet Patented Nov. 7, 1939 UNITED STATES PATENT FFICE PRESSUREREGULATING AND REDUCING APPARATUS George H. Smith, Kenmore, N. Y., andWilgot J. Jacobsson, Scotch Plains, N. J., assignors to The Linde AirProducts Company, a corporation ol' Ohio 13 Claims.

This invention relates to pressure regulating and reducing apparatus andmore particularly relates to improvements in apparatus employing a pilotregulator to control the pressure delivered by a main regulator. y

When regulating and reducing apparatus is employed in connection with anoxygen cylinder, the low temperature gas which is supplied from thecylinder prevents the proper operation of valves and diaphragms ofrubber composition of the kind used in prior type regulators. Thetemperature of converted oxygen gas is considerably below 5 C., thepoint at-which rubber loses its resiliency and tends to become glassyand brittle. It is necessary therefore to substitute for the rubberparts of the regulator some material that will be unaffected byextremely low temperatures.

Metal may be used in place of rubber in the valve seats and diaphragmsin'prior types of regulators, but a tight sealing effect in the valvescannot be accomplished in such regulators unless there is an exactalignment between the valve and the seat. Perfect axial alignment ofthevalve parts requires great accuracy of machine work and entailsprohibitive costs of manufacture.

It is an object of this invention to provide in a pressure regulatingand reducing apparatus all metal valve parts that will seal tightlywithout necessitating exact axial alignment.

It is a further object of this invention to provide in a pressureregulating and reducing apparatus a separate pilot regulator body sothat the pilot valve parts may be easily accessible for cleaning andrepair.

The above and other objects together with the novel features of thisinvention will be apparent from the following description and theaccompanying drawings, of which Fig. 1 is a full view of the apparatuswith a section cut away disclosing the connecting nipplesbetween themain regulator and the pilot regulator;

4.5 Fig. 2 isa cross sectionof the main regulatorshowing,the-valveconstruction; I '2-1 Fig. 3 is a side view oftheassembledfrappa- Figmi is an. enlargedview lshowing ,a cross section ofthe pilot regulator.; and

Figs. 5 and 6 are views fshowing the-frictional rlngrwhich is-employedto dampen the actionk of themain valve.

The regulatingand" reducing apparatus comprises a main regulator M and apilotregulator P so interconnected that pressure delivered by the pilotregulator governs the main regulator. The main regulator has aninlet Iand an outlet 2 connected by a port 3 which is controlled by a mainvalve V. The inlet I and the outlet 2 are 5 also connected by a by-passd leading through the pilot regulator and controlled by a pilot valve T.The control pressure delivered by the pilot regulator is directedthrough a passageway or tubing 5 to a main valve operating diaphragm 10D.

The main regulator M may comprise a body 6 and a cover '1. A partition 8in the body separates an inlet chamber A from an outlet chamber B andhas a central opening 9 for receiving 15 a nozzle II). The nozzle isprovided with a large diameter bore or port 3 and with a hexagonalshoulder having a raised sealing surface or valve seat II. The nozzlemay be threadedly secured within the opening 9 by cooperating screw 20threads I2 and I3. A bore I4 may be made in the wall of the body 6 inalignment with the nozzle I0 for guiding a valve head retainer I5, valvehead I6 and closing spring Il.

In accordance with this invention the valve 25 head I6 comprises arelatively thick metal disc having a raised annular sealing area or faceI of substantially the same diameter and width as the valve seat I I.The edge of the valve head I6 has a convex curvature. It ts within a re-30 cess in a cage I9 having a concave curvature which receives theconvex curvature on the valve head I6 and which forms a part of thevalve head retainer I5. The side of the valve head I6 opposed to thevalve face has a raised central 35 portion that is provided with aconvex surface 20 bearing against a iiat area of the valve head retainerI5. Valve head I6 is therefore slightly rockable within the retainingcage I9 so that the annular valve face I8 and valve seat II may 40 bebrought into uniform contact even though the plane of the valve face andthe plane ofthe valve seat may not have been parallel with each otherwhen the valve was assembled.

f 'I-'heA valveheadretainerfl mayhave a number4 4x5 of spaced f annular,ribs v2l for reducing the fric-v; tion betweemthe-wah of the bore I4`andthe retainer,,whenv the,retainer is moved lby the spring` I'l :inopeningfand closing the main port.P Theribsactgto' makewthe'boreself-cleaning." 50 Near the outer end .of the-retainer al groove-22is made for receivingan` annular friction .ring 23-. The ring 23. is.bent sinusoidally at several points .in the circumference -withoutaltering itsy annular shape but so `as to t tightly-within the groove.The ring bears longitudinally against the opposed side walls of thegroove, and bears radially against the Walls of the bore I4. The ringslides frictionally in the bore I4 and is free to rotate about the seatretainer, producing a substantially constant amount of friction toprevent chattering of the main valve. A suitable cap 24 may be providedtol close oi the outer end of the bore I4. A recess in the under side ofthe cap and another recess in the valve head re` tainer receive andsupport the opposite ends of the compression spring I1. The spring I1 iscomparatively weak in order that the effect of spring pressure on theaction of the main valve may be reduced.

The main regulator body 6 is provided with an annular rim 25 having itscenter axis in alignment with the nozzle IIJ and the bore I4. A cover,as a curved cover 1, may be mounted on the rim 25 and clinch the outeredge of the main operating diaphragm D between a rounded lip 26 on therim and a cooperating annular edge 28 on the under side of the cover.When so positioned, suitable stud bolts 29 may be screwed into tappeddrillings 3D in the rim 25 and nuts 3l may be employed to bring the bodyand cover tightly together. The diaphragm D forms a chamber 32 under thecover and a space 33 between the body 6 and the diaphragm. The latterspace 33 is connected with the outlet chamber B by a port 34 s'o thatdelivery pressure may act against the diaphragm D. The diaphragm issupported against excessive flexing by plates 35 and 36 which are joinedtogether by means of a stud 31, forming an integral part of the plate35, and by a nut 38. Each of the plates has a central hub. Between thesehubs the diaphragm D is clamped when the nut 38 is tightened on the stud31. A

raised annular lip on the outer edge of each plate acts as a partialstop tothe flexing action of the diaphragm when under pressure.

A drilling 39 is made in the wall of the body between chamber B andspace 33 and in alignmerit with the valve port 3. A oating valve stem 40slides within the drilling 39 without appreciable friction and extendsfrom the base of plate 35 to the valve head I6. When the valve V isclosed, the stem 48 bears lightly against the diaphragm supportingplate, and the diaphragm D maintains a normal nat position. A number ofrectangular vanes 6I may be welded to the stem 46'where it passesthrough the nozzle or port 3 in order to align the stem centrallyagainst the valve head I6. The guiding vanes slide against the wall ofthe port 3 and move with little or no friction when the valve isoperated.

As shown. in Fig. 1 an opening 4a is made in the wall of inlet chamber Afor communicating with the pilot regulator P, and an opening 4b is madein the wall of outlet chamber B for completing the by-pass 4 around themain valve V from the inlet chamber A to the delivery chamber B throughthe pilotregulator, The openings 4a and 4b are counterbored so as toreceive one end of the bevelled nipples 42 and 43. A suitable packingmaterial 45 is provided in the counterbores or countersunk recesses andis compressed by the beveled ends of the nipples to form gastight iointswhen the regulators are assembled. 'I'he other ends of the nipples 42and 43 are connected to the pilot regulator P. n The pilot regulator Pas shown in Fig. 4 comprises a body 46 preferably cylindrical in shapeand provided with lugs 41, 48 and 49 for attaching the' body 46 to themain regulator body 6 with stud bolts and nuts. The inlet nipple 42extends through a drilling 59 in the body adjacent the main regulatorand is supported at the closed end by a recess in the opposing wall. Thebore of the inlet nipple provides an inlet chamberfor the pilotregulator. A ilange 5I on the nipple forms a shoulder which is welded orotherwise cured to the pilot regulator body. The bypass passage 4 in thenipple is tapped at the inlet end to receive a screen retainer 52 and ane mesh wire screen 53 for removing foreign particles from the gas. Asmall nozzle 54 is screwed into a tapped drilling in the upper side ofthe nipple to provide a communication between the passage in the nippleand the pilot delivery chamber C.

The pilot regulator comprises also a valve mechanism operated by a pilotdiaphragm 56, and a pressure responsive mechanism operated by asecondary diaphragm 51 and an adjustable spring 58. The pilot valvemechanism and the. pressure responsive mechanism are interconnected. bya yoke 59 so that movements of the secondary diaphragm 51 and theadjustable. spring 58 also operate the pilot valve.

The pilot valve mechanism may comprise a valve head 60 having aralsedsealing area or valve face 6l and a convex base 62 as on the mainvalve head I6. The valve face 6I cooperates with a valve seat on thenozzle 54 when the pilot valve is closed. A valve retaining member Tprovided with a concave recess 63 holds the valve seat rockablypositioned so that the seat may adjust itself and make full contact withthe nozzle although not in exact alignment as in the case of the mainvalve V. A threaded area on the retaining member T is screwed into acylindrical portion of the yoke 59 by means of an upwardly extendingstem provided with a screw slot 64. A light valve closing spring 65 issupported between the stem and cylindrical wall of the yoke and iscompressed against a suitable cap 66 having a shallow drilling 61 forholding the end oi' the spring.

The yoke 59 is kept in a central position in the pilot regulator by anannular p erforated diaphragm 68 fitting around the upper end of theyoke and resting against a shoulder 69 thereof and a correspondingshoulder 10 in the body 46. Spring wire retaining rings 1I and. 12respectively support the diaphragm 68- against the inner and outershoulders. 'I'he yoke is shaped so as to pass around the nipple 42 andhave its upper end and its lower end centrally aligned within the pilotregulator. 'The lower end of the yoke supports the pilot diaphragm 56 bymeans of a cooperating nut 13. The outer edge of the pilot diaphragm issupported against a slightly beveled shoulder 14 in the body 46 by aclamping ring 15. The clamping ring may be externally threaded tocooperate with an internally threaded portion below the shoulder 14 inthe body 46, and may be provided with a curved area 16 contacting theunder side of the pilot diaphragm and forcing the outer edge thereofagainst the beveled shoulder 14 vin the body. When so clamped the outeredge of the diaphragm will bend readily under pressure exerted fromabove. Diametrlcally opposed slots 11 are made in the clamping ring inorder to screw the same into place. The end of the yoke rests within aclose fitting. cup-shaped washer 18 having a stem 19. A chamber C ismade in the upper part of the pilot regulator by the pilot diaphragm,and in order to complete the by-pass from nipple 42 to nipple 43 anaxial drilling is made in the lower end of the yoke Il and a smallbleeder passage 8| is drilled radially in the side oi the yoke below the-nut 13. p

The secondary or pressure-responsive diaphragm 51 is .supported at thecenter by the stem s 1l oi' washer 'I8 and by a guiding member 82. Theguiding member 82 has a shallow hole in the center ior receiving thestem 1I, and a raised upper'area II which bears against a substantialpart of diaphragm l1. The under side of guiding member 10 Il may beprovided with a shoulder 84 resting on the upper end oi' the adjustablespring il. A cap Il enclosed the spring Il and bears against a beveledshoulder Bl in the body when threadedly connected by screw threads 81and Il. 'I'he annular end o! the cap is similarly beveled and clamps theouter edge oi diaphragm l1 against the shoulder Il so that the diaphragmtends to bend downward when the valve is in a closed position. The wallci' the cap Il is of greater idth than the n shoulder il and supports anad tional area on the under side of the diaphragm. The unsupported areaof the secondary diaphragm l1 is slightly greater than that of the pilotdiaphragm Il, allowing nuotuations of pressure in the space Il betweenthe two diaphragms to have a greater enact on the secondary diaphragmthan on the pilot diaphragm Il. Thus, the eilective area of the portionoithe diaphragm Il that is exposed to the action of pressure within thechamber below lo the diaphragm Il is less than the en'ectlve area o! theportion oi the diaphragm l1 that is exposed to pressure .within the samechamber.

The cap l! may have a shoulder Il extending under the outer edge oi theguiding member Il as and. acting as a stop to hold the member in placeagainst the end of the yoke when not under pressure of the adviustingspring Il. The oep is preferably provided with a nulnber of breatherports 9 9 which adniit atmospheric pressure tothe under 4g side etdiaphragm Il. The spring may be a relativo strong helical coil oi springwire compressed between the K ding member and a spring adiusting washerl in order to vary the compression ei spring is, the spring adjustingwasher has a u sheulderbcaring against the end of the spring and aninner cylindrical bore provided with a ebaniiered base c! against whicha threaded stem l! niet be screwed. The stem Il cooperates with adrilled and tapped opening Il in the end of the l@ ed? and has aconvenient nut at the outer end for ad listing the position ci the steinand the spring. The end of the stein bearing against the washer l!!isinachlned to iorln a s oelget for holding a bali bearing that reducesirictionat this point. A gg ring washer 9s is secured to the stem nearthe upper end in order to prevent the stein irene being screwed out sithe cap when the sprln'gis dcccin= prenoti. A suitable loelr nut l1 :naybe employed e maintain any desired setting ci the adgustable ne niaiseliainber in the pilot regulator is connected with the ehenaber Ilbetween the cover andthe niain diaphragm h in the inain regulator sethat pressure delivered bv the pilot valve may ed eet en the in ain diehrasm D. A drilling Il is made in the side oi e inber d and a drillingIl is iliade in the sideef the cover 1, which drillings are tapped toreceive elbows or nipples Ille and lol that nies be interconnected by atube l. suitable ie daring nipples ina? be welded to either end ofthetube, and unlon nttings ,Ill and les may be elnployed in completing theconnections The valve heads and nasales in both regulators arepreferably puede oi a nitrided ferrous alley gs that provides sealingsuriaces or hard wearing,

non-corrodible or corrosion-resistant metal. 'I'he valve face and thevalve seat are ground to optical ilats to' insure a complete line ofcontact between the valve face and the seat at all points around theface and the seat. It is also preferred to use 5 a iexible sheet of a.suitable non-corrodible (corrosion-resistant) metal or alloy such asEverdur for the diaphragms.

In constructing the valve parts the ratio between the area within theseal or line of contact 1 0 between the valve face and its seat and thearea of the active portion of the diaphragm in each regulator is `madesubstantially equal. Thus, the ratios between the eilective seating areaol each of the respective valves and the effective area of the 1.5diaphragm associated therewith that is directly acted upon by thepressure existing in the chambers C and 32 are substantially equal. .Theactive area of the diaphragme relates to the area eilected by pressure.The main and pilot valves are conzo structed to open in oppositedirections in respect to the i'low oi the iluid therethrough. When themain regulator and the pilot regulator valves are so constructed and areproportioned in respect to their diaphragme as stated, the pressuredelivered 2o by the pilot valve to regulate operation of the main valvewill compensate for the eil'ects Aol' changes in inletpressure, and themain regulator will deliver a substantially constant pressure. In thepreferred form oi' apparatus, as shown,the so pilot valve is constructedto open with inlet pressure so that the delivery pressure in the pilotchamber falls with a falling inlet pressure. This characteristic isherein called a falling discharge characteristic. The main valve isconstructed to se open against inlet pressure so that a falling inletpressure on the main valve tends to increase the main delivery pressure.This tendency is called a rising discharge characteristic. The effect oithe falling characteristic of the pressure delivered to so the mainoperating diaphragm chamber 82 by the pilot regulator countcracts therising discharge tendency of the main valve and causes the apparatus todevelop a substantially constant discharge characteristic, or constantdelivery pressure regardless of a falling inlet pressure.

The pressureresponslve mechanism including the secondary diaphragm B7reacts to changes in he ilow of gas in the outlet chamber B of the mainregulator. These changes, which are momentary pressure variations, arecommunicated tc the diaphragm l1 and immediately adjust the position cithe pilot regulator valve so that the :nain regulator delivers a greateror smaller volunie of gas without substantially ail'eoting the es outletpressure.

Although we have described a preferred form of this invention it vshouldbe understood that changes may be inode in the form as shown withoutdeparting from the scope of this invention as co set iorth in theappended claims.

This application is a division oli our application Serial No. Senseo,filed January 3l, 1988, now Patent No. 2,082,223,1ssued on June l, i937.s

We claim: oo

l. Fressure regulating and reducing apparatus comprising, incombination, a tubular casing: a nexiblo diaphragm dividing said casinginto a primary-delivery chamber and a secondary delivery chalnber: asecond flexible diaphragm iorniing one wall ci said secondary deliverychamber; a tubular member extending transversely ci said casing; anozzle member mounted in said tubular member and forming a valve seat;valve' means adapted to cooperate with said nozzle 7l member forcontrolling the ilow of uid through said tubular member; resilient meansoperatively associated with each of said diaphragms for opposingmovement in one direction of said valve means; and a second resilientmeans for opposing both the. action 'of said first-named resilient meansand the action of iluid pressure withinsaid chambers.

2. The combination claimed in claim 1, in which said second resilientmeans is adjustable and is axially aligned with said first-namedresilient means.

3. The combination claimed in claim 1,v including means establishingrestricted communication between said chambers.

4. Pressure regulating and reducing apparatus comprising a pilotregulator housing adapted to be detachably mounted upon a main regulatorhousing; said pilot regulator housing having an inlet, a primarydelivery chamber, and a secondary delivery chamber, a pilotvalveseparating the pilot inlet and primary delivery chambers; a primarydiaphragm separating the primary delivery chamber and secondary deliverychamber and forming a wall oi the latter; and a secondary diaphragm ofgreater eiective area than the said primary diaphragm and forminganother wall of the secondary delivery chamber;

means integral with the pilot regulator housing for operativelyconnecting the pilot regulator inlet to the inlet of a main regulator;means integral with the pilot regulator housing .for operativelyconnecting the said secondary delivery chamber with the outlet of a mainregulator; a detachable conduit exterior of the said h'ousing foroperatively connecting the said primary de.- livery chamber to thepilot-controlled chamber of a main regulator; and mechanism fordetachably mounting the said pilot regulator housing upon a mainregulator housing and detachably securing the -said means in a mainregulator housing.

5. Apparatus as defined in claim 4 wherein eachl of the respectivediaphragms is made of flexible non-corrodible metal.

6. Apparatus-as dened in claim 4 wherein the said primary diaphragm andsecondary diaphragm in the pilot regulator housing are operativelyconnected respectively with the pilot valve.

'7. Apparatus as dened in claim 4, together with means having therein arestricted orice and connecting the primary delivery chamber andsecondary delivery chamber of the pilot regulator.

8. Apparatus as dened in claimf4 wherein the said valve is provided witha valve head of hard, Wearand corrosion-resistant metal.

9. Apparatus as defined in claim 4 wherein the said valve is providedwith a rockably-supported valve head.

10. Apparatus as detlned in claim 4 wherein each of the said means is anipple welded to the said pilot regulator housing and having unthreadedportions extending outwardly beyond the said housing and adapted to besecured within a corresponding passageway in the main regulator housing.

11. A pressure regulator comprising as a unitary structure a casinghaving an inlet, a primary outlet, and a secondary outlet; a valve and avalve seat in said casing; resilient means adapted to open the saidvalve; resilient means adapted to close the valve; a exible diaphragmoperatively interposed between said valve and said secondary outlet; asecond ilexible. diaphragm operatively interposed between thefirst-named diaphragm and said outlet and separating the interior of thecasing into a primary chamber and a secondary chamber; the area of thesaid second diaphragm subject to pressure within the said secondarychamber being greater than the area of the first-named diaphragm subjectto the said pressure; and a bleeder passage establishing communicationbetween said primary and secondary chambers; the said inlet and outlethaving integral therewith nipples provided with tapered marginsextending outwardly upon the casing.

12. A pressure regulator comprising as a unitary structure a casinghaving an inlet, a primary outlet, and a secondary outlet; a valve and avalve s'eat in said casing, the said valve opening with inlet pressure;resilient means adapted to open .the said valve; resilient means adaptedto close the valve; a flexible diaphragm operatively interposed betweensaid valve and said secondary outlet; a second ilexible diaphragmoperatively interposed between the iirst-named diaphragm and said outletand separating the interior of the casing into a primary chamber and asecondary chamber; the area of the said second diaphragm subject topressure within the said secondary chamber being greater than the areaof the iirstnamed diaphragm subjectvto the said pressure; and a bleederpassage establishing 'communication between said primary and secondarychambers; the said inlet and outlet having integral therewith nipplesprovided with tapered margins extending outwardly from the casing.

13. A pressure regulator comprising as a unitary structure a casinghaving an inlet, a primary outlet, and a secondary outlet; a valve and avalve seat in said casing; resilient means adapted to open the saidvalve: resilient means adapted to close the valve; a flexible diaphragmoperatively interposed between said valve and said secondary outlet; asecond exible diaphragm operatively interposed between the rst-nameddiaphragm and said outlet and separating the interior of the casing intoa primary chamber and a secondary chamber; the area of the said seconddiaphragm subject to pressure within the said secondary chamberA beinggreater than the area of the ilrstnamed diaphragm subject to the saidpressure; a conduit operatively connected with the said valve and havingtherein a constriction and establishing communication between saidprimary and secondary chambers; the said inlet and outlet havingintegral therewith nipples provided with tapered margins extendingoutwardly from the casing.

GEORGE H. SMITH. WILGOT J. JACOBSSON.

